A.J. Tolland
Aug17-04, 10:30 AM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n\nOn Sat, 14 Aug 2004, A.J. Tolland wrote:\n\n> It\'s often difficult to write down a theory with explicit symmetry\n> without also introducing a gauge symmetry... should we regard this as\n> simply an artifact of quantization?\n>\n> [Moderator\'s note:\n\n\n> Otherwise in field theory I disagree with you; it is very easy to\n> construct theories with global symmetries which are not local. For\n> example, the Standard Model with identical masses across the generations\n> has a generational SU(3) which is not local. LM]\n\nI said it is \'often hard\', not that it is never possible.\nI find it interesting that we have such difficulties writing down\n(super)Lorentz invariant QFTs of objects with spin > 1/2 without the\nintermediate step of gauge redundancies.\nIf you want to explain this peculiarity by saying that Lorentz is\nalways extended to diff, that\'s fine. Maybe even a nice piece of evidence\nfor string theory.\n\n--A.J.\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>On Sat, 14 Aug 2004, A.J. Tolland wrote:
> It's often difficult to write down a theory with explicit symmetry
> without also introducing a gauge symmetry... should we regard this as
> simply an artifact of quantization?
>
> [Moderator's note:
> Otherwise in field theory I disagree with you; it is very easy to
> construct theories with global symmetries which are not local. For
> example, the Standard Model with identical masses across the generations
> has a generational SU(3) which is not local. LM]
I said it is 'often hard', not that it is never possible.
I find it interesting that we have such difficulties writing down
(super)Lorentz invariant QFTs of objects with spin > 1/2 without the
intermediate step of gauge redundancies.
If you want to explain this peculiarity by saying that Lorentz is
always extended to diff, that's fine. Maybe even a nice piece of evidence
for string theory.
--A.J.
> It's often difficult to write down a theory with explicit symmetry
> without also introducing a gauge symmetry... should we regard this as
> simply an artifact of quantization?
>
> [Moderator's note:
> Otherwise in field theory I disagree with you; it is very easy to
> construct theories with global symmetries which are not local. For
> example, the Standard Model with identical masses across the generations
> has a generational SU(3) which is not local. LM]
I said it is 'often hard', not that it is never possible.
I find it interesting that we have such difficulties writing down
(super)Lorentz invariant QFTs of objects with spin > 1/2 without the
intermediate step of gauge redundancies.
If you want to explain this peculiarity by saying that Lorentz is
always extended to diff, that's fine. Maybe even a nice piece of evidence
for string theory.
--A.J.